Ageing, Hypertension and Aortic Valve Stenosis: A Conscious Uncoupling

Aortic valve stenosis (AS) is no longer considered to be a disease of fixed left ventricular (LV) afterload (due an obstructive valve), but rather, functions as series circuit with important contributions from both the and ageing vasculature. Patients AS are frequently elderly, hypertension markedly remodelled aorta. The arterial component sizable, yet, contribution has been difficult determine. Arterial stiffening increases speed propagation blood pressure wave along central arteries (estimated pulse velocity), which results in earlier return reflected waves. effect augment proximal aorta during systole, increasing and, turn, placing even greater on heart. Elevated global LV known have adverse consequences remodelling, function survival patients AS. 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It relating corresponding components acquired simultaneously artery site. forms graph modulus (amplitude divided flow) (time delay represented angle) plotted [[34]O'Rourke Over time, physiologists clinicians sought re-integrate knowledge physical sciences AS.Aortic input (ZIN) describes particular beyond depends vessels bed beyond. (ZC) these influenced usual ZC averaging moduli band where expect fluctuations cancel oscillations below, expressed Scholar].For spectrum performed domain, decomposed their harmonics fast Fourier transformation (FFT) frequencies up 10 Hz. Any typically excluded if less 0.6 mmHg cm/s velocity. take account rate (HR) measurements, normalised interpolated linearly nearest integer frequencies, 1, 2, 3 continuing Total resistance modules 0 Hz, routinely estimated mean magnitude 2 Hz.Age Valvulo-Arterial LoadPrior compliance, recently, ZVA, surrogates load. None indices, consider effects resistive separately hydraulic definition, includes steady components. Pulsatile closely conduit vessels. Stiffer lead faster ejected reflections branch points, augmenting yielding afterload. Steady-state best (SVR), whereas ZIN, ZVA-INS VAL setting Scholar,[21]Soulat Scholar,[22]Hungerford patterns younger patien